Pharmacology Lecture 1 Flashcards
What is a drug?
a biologically active compound that used in the prevention, alleviation, treatment and cure of a disease. Drugs are exogenous substances because it is not produced by the body (i.e. a hormone).
What is a receptor?
Receptors in the body help drugs bind as a means to help communicate, facilitate/prevent a biological action.
What is a specialized receptor?
Receptors can be many things, for example a specialized structure like a protein designed to bind for a specific drug. (ex: transcription factors or g -coupled protein receptors)
What are generalized receptors?
A generalized receptor is not a specific protein designed to bind, but rather it is a standard in a molecules function. It can be modified by the drugs interaction.
Where are receptors found?
They are found in the entire body, and each vary in structure, response and expression.
What is the “2nd” messenger cascade?
What receptors do once activated and how they change or facilitate physiological function.
How does a drug know where to bind?
When drugs enter the body they do not know where to go. Ideally they bind to a receptor that has a “snuggly” binding site.
Receptors and drugs have chemical-structure dependent reactions.
What is a drug-receptor complex?
This is accomplished when a drug is able to bind to a receptor and form a complex, much like enzyme substrates.
What determines how well a drug will work?
How well it fits in the receptor (a toothpick cant open a lock as well as a key can)
Are receptors used by endogenous compounds?
Yes, sometimes exogenous compounds such as those taken for medical conditions, can modify, inhibit or mimic an endogenous process.
What can influence drug and receptor interactions?
- chemical structure (larger drugs struggle to cross the membrane)
- chemical charge (uncharged molecules can only pass)
- polarity (hydrophobic)
How does the similar chemical structure of the drug help?
molecules that often have similar structures to endogenous compounds can simulate a response in the body. For example: Ventolin looks like Adrenaline and can bind to allow for relaxation of bronchial structure.
Drugs that have receptor affinity and intrinsic activity are known as…?
Agonists. They can activate receptors and cause a response.
Drugs that only have receptor affinity are known as…?
Antagonists. They do not activate the receptor as they are inhibitors. Antagonists can still cause a biological response by occupying the receptor and outcompeting endogenous compounds.
Give an example of this antagonistic relationship?
Claritin blocks the histamine receptor and prevents the histamine from triggering allergies
